When a man is performing sexual intercourse with a woman doggy style, the man spits on the woman's back in order to trick her into think he has ejaculated. When the woman turns around to check, the man quickly ejaculates on her face whilst throwing a handful of pubes at her.

Jane: Why does Mandy have pubes stuck to her face?
Steve: Jim found out she was cheating on him last night, so he decided to give her a bit of Guerilla Warfare